This invention relates to methods and apparatus for picture or image processing to improve the quality and viewing comfort of three dimensional ("3D") movies and other video systems.
Conventional 3D motion picture systems typically require two movie cameras (or a compound camera), stereoscopically related and synchronized together, to photograph a scene. The two cameras are usually positioned side by side to correspond with a viewer's left and right eyes. When the stereo pictures are reproduced on the viewing screen, usually one is projected with vertically polarized light and the other is projected with horizontally polarized light. The two pictures are projected on the same screen, superimposed on each other. The viewer uses special glasses with polarized filter lenses such that the left lens filters out the right camera picture and the right lens filters out the left camera picture. Thus, the left eye views only the left camera picture and the right eye views only the right camera picture.
The resulting picture usually presents an excellent illusion of three dimensional depth, and adds much realism to the movie. However, despite the positive effects of the 3D illusion, the technique has generally been unsuccessful at the box office. Every ten years or so, a few 3D movies are produced. But each time such movies have proven to be unsatisfactory and uncomfortable to the viewers and have generally proven to be financially unsuccessful.
The reason often cited for the lack of success of 3D movies is that the special glasses are too uncomfortable for the viewer. It may be, however, that the glasses are not prohibitively uncomfortable, but rather, that it is what the viewer sees with the glasses that is uncomfortable and visually tiring for the viewer.
The stereo camera arrangement described above is able to reproduce the conditions required for stereopsis (binocular fusion) to take place. However, such a camera arrangement is not able to adequately reproduce other conditions required for other elements normally involved in the human binocular perception of depth. The elements involved include, in addition to binocular fusion, binocular convergence (and the human convergence control system) and accommodation.